The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
In recent years, with the development of semiconductor manufacturing technologies, a process of a thin film transistor (TFT) becomes increasingly simple and fast, so that TFTs are widely applied to computer chips, mobile phone chips, TFT liquid crystal displays (LCD), and the like. A common method for manufacturing a TFT is back channel etch (BCE), which includes the following steps: first forming a metal layer covering an active layer, and then patterning the metal layer to form a source and a drain, where the step of patterning may be performed by using wet etching or dry etching. However, after an etchant removes the metal layer on the active layer, the active layer is highly vulnerable because of exposure to the etchant, causing a yield of TFTs to reduce.
In view of this, a method for manufacturing a TFT in which an active layer can resist corrosion by the etchant and a structure that is formed by using this method are needed.